使用JavaScriptSerializer()反序列化JSON文件

Question

我将反序列化的json文件的结构如下所示;

{
    "id" : "1lad07",
    "text" : "test",
    "url" : "http:\/\/twitpic.com\/1lacuz",
    "width" : 220,
    "height" : 84,
    "size" : 8722,
    "type" : "png",
    "timestamp" : "Wed, 05 May 2010 16:11:48 +0000",
    "user" : {
        "id" : 12345,
        "screen_name" : "twitpicuser"
    }
}

我创建了一个类,其字段名称为JavaScriptSerializer的属性.我将用于反序列化json的代码如下:

            using (var reader = new StreamReader(twitpicResponse.GetResponseStream())) {


                var responseBody = reader.ReadToEnd();
                var deserializer = new JavaScriptSerializer();
                var results = deserializer.Deserialize<Response>(responseBody);

            }

我的问题是我如何读取json文件上的用户字段.这就像下面;

"user" : {
    "id" : 12345,
    "screen_name" : "twitpicuser"
}

它有子属性和值.我怎样才能在我的Response类中命名它们.我的回复课现在看起来像这样;

public class Response {

    public string id { get; set; }
    public string text { get; set; }
    public string url { get; set; }
    public string width { get; set; }
    public string height { get; set; }
    public string size { get; set; }
    public string type { get; set; }
    public string timestamp { get; set; }

}

这样做最好的情况是什么？

Answer 1

1. 您需要创建一个包含用户值的类,就像响应类一样User.

2. 使用用户值的新类的类型向Response类'user'添加属性User.

   public class Response {
   
       public string id { get; set; }
       public string text { get; set; }
       public string url { get; set; }
       public string width { get; set; }
       public string height { get; set; }
       public string size { get; set; }
       public string type { get; set; }
       public string timestamp { get; set; }
       public User user { get; set; }
   
   }
   
   public class User {
   
       public int id { get; set; }
       public string screen_name { get; set; }
   
   }
   

通常,您应该确保json和CLR类的属性类型匹配.您尝试反序列化的结构似乎包含多个数字值(最有可能int).我不确定是否JavaScriptSerializer能够自动将数字反序列化为字符串字段,但您应该尽可能地将CLR类型与尽可能接近实际数据相匹配.

Answer 2

假设您不想创建另一个类,您始终可以让反序列化器为您提供键值对的字典,如下所示:

string s = //{ "user" : {    "id" : 12345,    "screen_name" : "twitpicuser"}};
var serializer = new JavaScriptSerializer();
var result = serializer.DeserializeObject(s);

你会得到一些东西,你可以做到:

var userId = int.Parse(result["user"]["id"]); // or (int)result["user"]["id"] depending on how the JSON is serialized.
// etc.

看看result在调试器中看到,里面有什么了.

Answer 3

对于.Net 4+:

string s = "{ \"user\" : {    \"id\" : 12345,    \"screen_name\" : \"twitpicuser\"}}";

var serializer = new JavaScriptSerializer();
dynamic usr = serializer.DeserializeObject(s);
var UserId = usr["user"]["id"];

对于.Net 2/3.5:此代码应适用于1级JSON

samplejson.aspx

<%@ Page Language="C#" %>
<%@ Import Namespace="System.Globalization" %>
<%@ Import Namespace="System.Web.Script.Serialization" %>
<%@ Import Namespace="System.Collections.Generic" %>
<%
string s = "{ \"id\" : 12345,    \"screen_name\" : \"twitpicuser\"}";
var serializer = new JavaScriptSerializer();
Dictionary<string, object> result = (serializer.DeserializeObject(s) as Dictionary<string, object>);
var UserId = result["id"];
 %>
 <%=UserId %>

对于2级JSON:

sample2.aspx

<%@ Page Language="C#" %>
<%@ Import Namespace="System.Globalization" %>
<%@ Import Namespace="System.Web.Script.Serialization" %>
<%@ Import Namespace="System.Collections.Generic" %>
<%
string s = "{ \"user\" : {    \"id\" : 12345,    \"screen_name\" : \"twitpicuser\"}}";
var serializer = new JavaScriptSerializer();
Dictionary<string, object> result = (serializer.DeserializeObject(s) as Dictionary<string, object>);
Dictionary<string, object> usr = (result["user"] as Dictionary<string, object>);
var UserId = usr["id"];
 %>
 <%= UserId %>